North Shore in third year of looper moth outbreak

Expect to see hemlock looper moths again this year, as the North Shore is in the third year of an outbreak that typically lasts three to four years.

Moths are already starting to appear on the North Shore and are expected to fly until October.

These moths are a native species and outbreaks are part of the natural coastal forest ecosystem that feeds on trees. You may notice some trees turning brown as a result of the moth outbreak and extreme heat this summer.

These moths primarily feed on western hemlock, Douglas-fir, and western redcedar trees, which is what causes trees to lose their needles and turn brown.

Over-mature trees are more susceptible to damage and may die due to moths feeding on them. This provides the right conditions for trees to come back greener than before, and can increase biodiversity and revitalize forests.

Trees that were already impacted by the moth outbreak have been further stressed due to the extreme heat this summer and are very dry.

Western hemlock looper moths cannot make you sick. Residents living near forests should clean the filters of their home ventilation systems to ensure air intakes are functioning properly.

Moth populations are dependent on weather and other environmental factors. It is unknown how higher temperatures caused by climate change will impact moth populations in the future.